Organo-phosphorus compounds



United States Patent 3,226,425 0RGANO-PHOS?HORUS COMPOUNDS Wayne T. Barrett, Malvern, Pa., assignor to W. R. Grace & Co., New York, N.Y., a corporation of Connecticut No Drawing. Filed June 30, 1964, Ser. No. 379,378 3 Claims. (Ci. 260-4658) The present application is a continuation-in-part of my prior applications Serial Nos. 764,531, filed October 1, 1958, and 154,063, filed November 21, 1961, now abandoned.

This invention relates to new organo-phosphorus compounds. In another more specific aspect, it relates to aminophosphonium compounds suitable as petroleum product additives.

fouling. Such fouling is prevalent in gasoline powered airplane engines and other gasoline internal combustion engines which operate at high temperatures. It has been found that the use of phosphoruscontaining compounds in conjunction with halogen-containing hydrocarbons will virtually alleviate spark plug fouling.

Gasoline and lubricating oils containing carbon-carbon unsaturation and other linkages are susceptible to oxidation. Such oxidation causes discoloration and breakdown of lubricating oils at operating temperatures and the formation of harmful deposits in gasoline and fuel oils even on standing. Of the many organic compounds used as anti-oxidants in petroleum products, those containing the NH (amino) group have been found to be exceptionally eifective in preventing undesirable oxidation.

The aminophosphonium compounds of this invention I are organo-phosphorus anti-oxidants containing the amino group. In addition, when the anion is a halogen, these compounds are also scavengers for leaded fuels. Since the three remaining valences of phosphorus contain hydrocarbon residues, these compounds blend Well with petroleum products and will cause no deleterious effects in an internal combustion engine when administered with the fuel in beneficial quantities. Thus, it is seen that the novel compounds of my invention are suitable as petroleum additives and exhibit scavenger, anti-fouling and anti-oxidant properties. Under ideal conditions, these desirable attributes may be combined all in one molecule thus alleviating the need for multiple additives.

It is therefore an object of the present invention to provide novel aminophosphonium compounds useful as additives for petroleum products.

It is yet another object of the present invention to provide a new class of organic anti-oxidants.

These and other objects and advantages will become obvious to those skilled in the art from the following disclosure. The novel compounds of this invention are defined by the structural formula:

mentioned above may typically contain 1 to about 20 carbon atoms while the alkenyl groups may possess from lstituted phosphine.

3,226,425 Patented Dec. 28, 1965 about 3 to 20 carbon atoms. X in the above formula represents an anion bearing the charge n, and n also represents the number of cations required to balance the anionic charge. Typical anions which X may represent are chloride, bromide, iodide, fluoride, hexafluorophosphate, perchlorate, anthraquinone-beta-sulfonate, nitro prusside, periodate, picrate, hexachloroplatinate and ferricyanate.

In accordance with the present invention, it has been discovered that chloramine reacts with substituted phosphines (trivalent organo-phosphorus compounds where all of the 3 valences of phosphorus are satisfied by organic substituents to form substituted amino-phosphinium chlorides) In the preferred practice of my invention, gaseous chloramine is bubbled through a solution of the phosphine in an unreactive solvent and to mix such a solution with the phosphine similarly dissolved.

While chloramine is most advantageously prepared as a gaseous chloramine-ammonia mixture obtained from a generator constructed according to the teachings of Sisler et al., U.S. Patent 2,710,248, other methods are equally adaptable for the purpose of my invention. For instance, chloramine may be made byJeacting chlorine with an excess of ammonia in carbon tetrachloride or similar halogenated'hydrocarbon solvents under controlled conditions of mixing at low temperatures. Such a process is fully described in U.S. Patent 2,678,258 to J. F. Haller. Another effective method presented by Coleman et a1. is fully described in Inorganic Syntheses, vol. 1, 59 (1939) and based essentially on the pioneer work of Raschig, Ber.,

The essence of my invention is the reaction of chloramine with the appropriate substituted phosphine. Other methods of contacting the reactants will suggest'themselves to those skilled in the art and fall within the scope of this invention. Neither the solvents used nor the emperature of reaction is crucial to this invention. But due to the highly exothermic nature of the reaction, it has been found to be most convenient to operate at temperatures between 0 and 25f. C. Maximum yields are obtained under the conditions employed here when the reaction mixture is chilled in an ice bath while chloramine is being added and then allowed to warm to room temperature. When the appropriate solvent is chosen, the product will be insoluble and will crystallize from the reaction mixture. If soluble, the product can be recovered by evaporation of the solvent. In any event, the

product is purified by recrystallization or by other stand- .ard techniques known to those skilled in the art. A necesin water, proceeds very slowly. I

It is obvious that not all of the novel aminophosphonium compounds of my invention are prepared directly by the reaction of chloramine with the appropriate sub;-

Compounds containing anions other than chloride are prepared by metathesis starting with the chloride and the compound containing the anion to be introduced. Many of the new compounds may be obtained by mixing aqueous solutions of the chloride with an aqueous solution of the appropriate compound and, more often than not, the desired product precipitates as the reaction progresses. This is the case when thenew 3 compound being formed is less soluble or insoluble in water. The hydrolysis of these compounds is so slow that methathesis occurs successfully in aqueous solutions. Other metathetical approaches are available and the method selected depends on experimental convenience, costs of reagents and the difference in physical properties between the product and the starting material to be utilized in their separation. Solvents other than water may be used and are convenient when the product is soluble but the inorganic salt formed is not. Quite often a mixture of the reagents may be heated in the absence of a solvent. Other approaches will suggest themselves to those skilled in the art.

The scope and utility of my invention is further illustrated by the following examples:

Example I Chloramine was prepared from an aqueous solution of ammonia and sodium hypochlorite essentially according to the method of Raschig, Ben, 40, 4530 (1907). The Chloramine was extracted with ether from the aque ous solution; the ethereal solution was dried and slowly added with shaking to an ice-cooled flask containing about a 10% solution of triphenylphosphine was highly exothermic and an excess of the triphenylphosphine was provided to eliminate the possibility of the product being destroyed by excess chloramine. Triphenylaminophosphonium chloride precipitated as a colorless crystalline solid. It was collected by filtration and purified by washing several times with ether, with minimal quantities of cold water and finally with benzene. The purified product, after drying, melted 230-232" C. and had an analysis corresponding to the chloramine adduct of triphenylphosphine having the structural formula:

The best sample analyzed: 68.50% C, 5.75% H, 9.78% P, 4.37% N, and 11.18% Cl. Theoretical analysis for C H PNCI: 68.90% C, 5.42% H, 9.89% P, 4.46% N and 11.32% Cl. Triphenylaminophosphonium chloride (not very soluble in cold but quite soluble in hot water) hydrolyzed slowly to form triphenylphosphine oxide when exposed to moisture.

Example 11 Triphenylaminophosphonium chloride Was further characterized by its conversion to a series of derivatives containing the triphenylaminophosphonium cation. When separate portions of freshly prepared saturated aqueous solutions of triphenylaminophosphoniurn chloride Were treated with aqueous solutions of potassium hexafluorophosphate, potassium perchlorate, sodium anthraquinonebeta-sulfonate, sodium nitroprusside and potassium periodate, the corresponding triphenylaminophosphonium salts precipitated from solution. The melting points and the analytical data on the compounds thus obtained are summarized below:

Tr-iphenylaminophosphonium hexafiuorophosphate, M.P. 165-167 C. Found: 50.90% C, 4.16% H, 3.32% N, 14.64% P and 26.70% F. Theoretical for 51.06% C, 4.02% H, 3.31% N, 14.60% P and 26.95% F.

Triphenylaminophosphonium perchlorate, M.P. 172- 173 C. Found: 57.30% C, 4.65% H, 8.05% N, and 9.34% Cl. Theoretical for [(C H P*NH ]ClO 57.22% C, 4.50% H, 8.21% P, 3.71% N and 9.40% Cl.

Triphenylaminophosphonium anthraquinone-beta-sulfonate, M.P. 214-216 C. Found: 68.05% C, 4.23% H, 5.23% P, 2.59% N, 5.61% S. Theoretical for 67.96% C, 4.25% H, 5.49% P, 3.48% N, and 5.66% C. Triphenylaminophosphonium nitroprusside, M.P. 193

195 C. Found: 63.59% C, 4.47% H, 8.63% P, 14.93% N and 27.19% 1. Theoretical for 67.96% C, 4.25% H, 5.49% P, 2.48% N and 5.66% S.

Triphenylaminophosphonium periodate, M.P. 163- 165 C. Found: 45.80% C, 3.57% H, 6.56% P, 3.11% N and 27.19% 1. Theoretical for 46.05% C, 3.62% H, 6.61% P, 2.90% N, and 27.07% I.

Also prepared and analyzed were triphenylaminophosphonium picrate (M.P. -125 C.), triphenylaminophosphonium hexachloroplatinate (M.P. 190-193 C.) and triphenylaminophosphonium f-erricyanide (M.P. C.).

Example 111 Using the above-described Sisler generator, chloramine was produced by the gas phase reaction of chlorine with ammonia. About 1.3 g. of chlorarnine was passed into 30 ml. of anhydrous tri-(n-butyl) phosphine held at about 0 C. over a period of 15 minutes. The reaction mixture was allowed to warm to room temperature (25 C.) as 1.3 gr. additional of Chloramine was added during a second 15 minute period. The resultant white solid was filtered in a dry atmosphere, washed twice with anhydrous ether and dried in a desiccator over phosphorus pentoxide. A yield of over 80% (based on the amount chloramine consumed) of tri-(n-butyl) aminophosphonium chloride (M.P. 55-59 C.) was obtained; it had an analysis consistent with the formula Using the method of Example II, tri-(n-butyl)aminophosphonium hexafiuorophosphate (M.P. 7274 C.), tri-(n- 'butyl) aminophosphoniurn picrate (M.P. 7173 C.) and tri (n butyl) aminophosphonium hexachloroplatinate (M.P. -141 C.) were prepared. Each compound, on analysis, gave excellent agreement with the values calculated for the compound.

Example IV The mixture of chloramine and ammonia produced by the gas phase chlorine-ammonia reactor was passed for 17 minutes into a solution of 5 g. of cyclotetr amethylenephenylphosphine dissolved in 35 ml. of ether at a temperature of 1520 C. A white crystalline product be gan to precipitate almost immediately. At the end of the chloramination (ca. 1.4 g. of chloramine used) the product (better than 80% yield based on the amount of chloramine used) Was collected by filtration in the absence of moisture, washed twice with anhydrous ether and dried under vacuum over Drierite. The product was soluble in water by sensitive to hydrolysis. The chemical analysis of the product corresponded to cyclotetramethylenylaminophosphonium chloride which has the structural formula:

c H.o H, C 5H5- P C] N Hg C I-Iz-C Hz Using essentially the method of Example II, cyclotetramethylenephenylaminophosphonium anthraquinone-betasulfonate (M.P. 205 C.) and cyclotetramethylenephenylaminophosphonium hexafiuorophosphate (M.P. 7677 C.) were prepared.

Example V Using the approach of Example IV, chloramine was reacted with triethylphosphine. White solid triethylaminophosphonium chloride formed in the reaction mixture. The product was extremely hygroscopic and melted at 77 C. in a sealed capillary tube.

Example VI Using the method of Example II, cyclopentamethylenephenylaminophosphonium hexafiuorophosphate, anthraquinone-beta-sulfonate and picrate were prepared. Each compound (including the chloride) gave excellent agreement on analysis with the values calculated for the compound.

Example VII Using the approach of Example IV, chloramine was reacted with triphenylphosphine. The white crystalline product melted 232234 C. and is the same triphenylaminophosphonium chloride prepared in Example I where the chloramine was made by the Raschig method.

Example VIII To a solution of 0.955 g. (3.14 millimoles) of tribenzylphosphine in 80 ml. of dry benzene at 25 was passed approximately 8.3 millimoles of chloramine in the form of the ammonia-chloramine gas mixture from the chloramine generator (rate of chloramine generation about 0.1 mole per hour). The resultant crystalline product was filtered, washed with dry benzene, and dried under vacuum (weight 0.745 g., 2.09 millimole calculated as (C H CHQ PNH CI). This, when recrystallized from hot chloroform, melted at 220221 and gave analytical results in agreement with the formula The tribenzylaminophosphonium ion was further confirmed by the preparation and analysis of the corresponding picrate and chloroplatinate salts. These salts were prepared by metathesis with alkali metal picrates or chloroplatinates in aqueous or ethanolic solutions.

Example 1X The gaseous efiiuent of a chloramine generator (approx. 5 millimoles of chloramine) was passed into a solution of 0.533 g. (2.76 millimoles) of tris-(2-cyanoethyl)phosphine in 80 ml. of dry methylene chloride at room temperature. The resultant crystalline solid was washed with dry methylene chloride and vacuum dried at room temperature (weight 0.581 g.). The identity of the principal constituent of the product was established by conversion, through metathesis, to the tris-(2--cyanoethyl)aminophosphonium picrate and the hexachloroplatinate, both of which Were purified and analyzed.

Example X To a solution of 2.91 g. (15.1 millimoles) diallylphenylphosphine dissolved in ml. dry ethyl ether, 25 millimoles of chloraminc in the form of a gaseous ammoniachloramine mixture from the chloramine generator Was added at 25. A light yellow, sticky solid formed on the sides of the tube. The reaction mixture was chilled to about -65 and the mother liquor decanted. The solid residue was washed with two 30 ml. portions of ethyl ether by decantation. The reaction tube and solid was kept cold and the solid scraped from the sides of the container (weight 2.94 g. or 12.16 millimoles calculated as About 3.0 g. (1.56 millimoles) of unreacted phosphine was recovered from the ether filtrate and washings. The solid product contained 15.72% C1 (by Volhard analysis). Calculated for CH =CHCH 2 (C l-I PNH Cl: 14.6% C1. The product is, therefore, slightly impure with traces of ammonium chloride. The yield of this product is about based upon phosphine reacted. To confirm the presence of the diallylphenylaminophosphine ion the chloride product was converted by metathesis to the anthraquinone-B-sulfonate and the hexachloroplatinate.

I claim:

1. Compounds of the formula wherein R is selected from the group consisting of cyanoalkyl having 1 to 20 carbon atoms, and alkenyl having 3 to 20 carbon atoms, and R and R are selected from the group consisting of alltyl having 1 to 20 carbon atoms, phenyl, cyanoalkyl having 1 to 20 carbon atoms, and alkenyl having 3 to 20 carbon atoms; and X is selected from the group consisting of chloride, bromide, iodide, fluoride, hexafiuorophosphate, perchlorate, anthraquinone-beta-sultonate, nitroprusside, periodate, picrate, hexachloroplatinate and ferricyanate.

2. The compound, tris-(2-cyanoethyl)aminophosphoniurn chloride.

3. The compound, diallylphenylphosphonium chloride.

No references cited.

CHARLES E. PARKER, Primary Examiner. 

1. COMPOUNDS OF THE FORMULA 